Immunophenotypic Aberrancies Do Not Seem to Represent a Negative Prognostic Factor in High-Grade Canine T-Cell Lymphomas
1Anicura Istituto Veterinario Novara, Granozzo Con Monticello, Novara, Italy; 2Dick White Referrals, Cambridge, England, UK; 3Department of Veterinary Sciences, University of Turin, Turin, Italy; 4Department of Comparative Biomedicine and Food Science, University of Padua, Padua, Italy; 5Anicura Centro Oncologico Veterinario, Sasso Marconi, Bologna, Italy; 6Davies the Veterinary Specialists, Higham Gobion Hitchin, England, UK; 7Langford Vets, Bristol, England, UK; 8Royal Veterinary College, University of London, London, England, UK
Introduction
Immunophenotypic aberrancies can be detected by flow-cytometry (FC), however, their prognostic significance in high-grade canine lymphoma remains unknown.
The aim of this retrospective study was to evaluate if the presence of immunophenotypic aberrancies carries a worse prognosis in dogs with high-grade T-cell lymphoma (TCL) treated with lomustine-based protocols.
Methods
Medical records from six institutions between 2010 and 2021 were reviewed. Dogs with a diagnosis of high-grade TCL through cytology and FC (that included antibodies for CD45, CD3, CD5, CD4, CD8, CD21, CD79a, MHCII, and CD34), and treated with lomustine-based protocols were included.
Information regarding stage, sub-stage, treatment type, response to treatment, progression-free survival (PFS), and median survival time (MST) were recorded. Immunophenotypes were considered aberrant when showing qualitative alterations in receptor expression: loss or diminished expression of expected antigens and/or co-expression of markers of different cell lineage.
Results
Fifty-five dogs met the inclusion criteria and were divided into two groups: aberrant group (AG) including 28 dogs, and non-aberrant group (NAG) including 27 dogs. Groups were considered homogeneous in terms of stage, sub-stage, and overall response to treatment (with AG having 89.2% of responders and NAG 88.8% of responders).
Median PFS time was 126 days for AG and 190 days for NAG (p=0.226). MST was 165 and 275 days for AG and NAG, respectively (p=0.205). No statistical differences were found in MST and PFS between dogs with aberrant and non-aberrant high-grade TCL.
Conclusion
Immunophenotypic aberrancies do not seem to represent a prognostic factor in our study population.
Funding Information
None.